X-ring rubber bullets have been around for more than a generation. Currently they are manufactured by the Meister Bullet & Ammunition Company. Boxes of 50 retail for around $12.

These should not be confused with “less lethal” or riot-control projectiles. Rather, these are reusable primer-powered training bullets. I tested both .38 and .44 caliber versions.

Because they are powered only be a primer X-rings carry very little energy: They certainly will not cycle an auto-loading action. But they function seamlessly in revolvers when correctly loaded: In order to prevent the detonating primer from jamming itself against a revolver’s breech face it is necessary to drill out the primer pocket’s flash hole to 3/32″ on .38 brass and 1/8″ on .44 or .45 brass. (Note that with these expanded flash holes that brass should never again be used with standard loads, so it’s important to mark and segregate brass for use with X-rings.)

Loading X-ring ammunition is simple: seat a primer, then push a bullet into the neck of the case by hand. The average .38 X-ring bullet weighs 7.7gr, and the average .44 X-ring weights 14gr. I tested the .38s out of my 2″ S&W 642 revolver and the .44s out of my 3″ S&W 629. Longer barrels will only decrease muzzle velocity since primers produce so little propellant gas.

On the .38 I tested both WSP and CCI 550 “Magnum” primers and didn’t detect any significant difference in velocity. On the .44 I used WLP primers. I measured the average velocity for each load at 5, 15, and 21 feet:

Distance	.38	.44
5 feet	450fps	440fps
15 feet	360fps	400fps
21 feet	300fps	330fps

Obviously these are not ballistically efficient projectiles. At these ranges they are as accurate as conventional ammunition, but even at 7 yards their point of impact has dropped almost a full foot due to their low velocity, which is decreasing so rapidly I don’t think they would be useful at much greater distances.

The great thing is that because they are so light the bullets will stop inside a cardboard box with a towel draped in the middle. They are reusable — the manufacturer claims that if they’re cleaned with silicone lubricant they are good for 75-100 firings. I didn’t see any degradation after shooting them five times. I noted that the first bullet through a clean barrel leaves a thin stripe of rubber against any sharp rifling, and that seems to buffer subsequent shots against wear.

It’s easy to clean a gun after shooting these: Any rubber peals away from the barrel with a single pass of a dry brush. However I was surprised at how dirty primers are: In the photo above you can see the fired nickel-plated case coated in a layer of soot, which also ends up in all the usual places on the gun. Immediately after testing I was able to wipe off all the fouling with a dry rag.

If you’re using conventional (lead styphnate) primers I would hesitate to shoot them in unventilated indoor spaces because this lead-laced fouling doesn’t all settle on the gun: It’s dispersed in the air, and it’s not good for you, especially if it accumulates in an enclosed space.

Finally a note of caution: These look like a tempting tool for close-quarters force-on-force training. Their impact energy is in the same league as a paintball, Simunition, or heavy air-soft pellet, which means that with adequate clothing and head protection these should in principle be safe to shoot at a real person. However, unlike those other projectiles X-rings fire from unmodified guns that are fully capable of shooting full-power ammunition. No matter how careful you are eventually a standard round will slip into a gun somebody thinks is loaded only with X-rings. Therefore, I would never fire these at a person, and I would always ensure my practice backstop can safely contain a real bullet.